;(function () {
  let iatWS
  let resultText = ''
  let resultTextTemp = ''

  /**
   * 获取websocket url
   * 该接口需要后端提供，这里为了方便前端处理
   */
  function getWebSocketUrl() {
    // 请求地址根据语种不同变化
    var url = 'wss://iat-api.xfyun.cn/v2/iat'
    var host = 'iat-api.xfyun.cn'
    var apiKey = API_KEY
    var apiSecret = API_SECRET
    var date = new Date().toGMTString()
    var algorithm = 'hmac-sha256'
    var headers = 'host date request-line'
    var signatureOrigin = `host: ${host}\ndate: ${date}\nGET /v2/iat HTTP/1.1`
    var signatureSha = CryptoJS.HmacSHA256(signatureOrigin, apiSecret)
    var signature = CryptoJS.enc.Base64.stringify(signatureSha)
    var authorizationOrigin = `api_key="${apiKey}", algorithm="${algorithm}", headers="${headers}", signature="${signature}"`
    var authorization = btoa(authorizationOrigin)
    url = `${url}?authorization=${authorization}&date=${date}&host=${host}`
    return url
  }

  function toString(buffer) {
    var binary = ''
    var bytes = new Uint8Array(buffer)
    var len = bytes.byteLength
    for (var i = 0; i < len; i++) {
      binary += String.fromCharCode(bytes[i])
    }
    return binary
  }

  function renderResult(resultData) {
    // 识别结束
    let jsonData = JSON.parse(resultData)
    if (jsonData.data && jsonData.data.result) {
      let data = jsonData.data.result
      let str = ''
      let ws = data.ws
      for (let i = 0; i < ws.length; i++) {
        str = str + ws[i].cw[0].w
      }
      // 开启wpgs会有此字段(前提：在控制台开通动态修正功能)
      // 取值为 "apd"时表示该片结果是追加到前面的最终结果；取值为"rpl" 时表示替换前面的部分结果，替换范围为rg字段
      if (data.pgs) {
        if (data.pgs === 'apd') {
          // 将resultTextTemp同步给resultText
          resultText = resultTextTemp
        }
        // 将结果存储在resultTextTemp中
        resultTextTemp = resultText + str
      } else {
        resultText = resultText + str
      }
      document.getElementById('result').innerText = resultTextTemp || resultText || ''
    }
    if (jsonData.code === 0 && jsonData.data.status === 2) {
      iatWS.close()
    }
    if (jsonData.code !== 0) {
      iatWS.close()
      console.error(jsonData)
    }
  }

  function connectWebSocket(callback) {
    const websocketUrl = getWebSocketUrl()
    if ('WebSocket' in window) {
      iatWS = new WebSocket(websocketUrl)
    } else if ('MozWebSocket' in window) {
      iatWS = new MozWebSocket(websocketUrl)
    } else {
      alert('浏览器不支持WebSocket')
      return
    }
    iatWS.onopen = (e) => {
      var params = {
        common: {
          app_id: APPID,
        },
        business: {
          language: 'zh_cn',
          domain: 'iat',
          accent: 'mandarin',
          vad_eos: 5000,
          dwa: 'wpgs',
        },
        data: {
          status: 0,
          format: 'audio/L16;rate=16000',
          encoding: 'raw',
        },
      }
      iatWS.send(JSON.stringify(params))
      callback()
    }
    iatWS.onmessage = (e) => {
      renderResult(e.data)
    }
    iatWS.onerror = (e) => {
      console.error(e)
    }
  }

  document.getElementById('input_file').onchange = (e) => {
    if (e.target.files[0]) {
      connectWebSocket(() => {
        const reader = new FileReader()
        reader.readAsArrayBuffer(e.target.files[0])

        reader.onload = (evt) => {
          console.log(evt.target.result)
          const audioString = toString(evt.target.result)
          // console.log(audioString.length, evt.target.result.byteLength)
          let offset = 0

          while (offset < audioString.length) {
            const subString = audioString.substring(offset, offset + 1280)
            offset += 1280
            // console.log(subString.length, subString)
            const isEnd = offset >= audioString.length
            iatWS.send(
              JSON.stringify({
                data: {
                  status: isEnd ? 2 : 1,
                  format: 'audio/L16;rate=16000',
                  encoding: 'raw',
                  audio: window.btoa(subString),
                },
              }),
            )
          }
          // const interval = setInterval(() => {
          //   const subString = audioString.substring(offset, offset + 1280)
          //   offset += 1280
          //   // console.log(subString.length, subString)
          //   const isEnd = offset >= audioString.length
          //   iatWS.send(
          //     JSON.stringify({
          //       data: {
          //         status: isEnd ? 2 : 1,
          //         format: "audio/L16;rate=16000",
          //         encoding: "raw",
          //         audio: window.btoa(subString)
          //       },
          //     })
          //   );
          //   if (isEnd) {
          //     clearInterval(interval)
          //   }
          // }, 20)
        }
        reader.onerror = () => {
          iatWS.close()
        }
      })
    }
  }
})()
